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Tuesday, 25 November 2014

85 mm Guns

Rival D-5 and S-31 guns might appear identical to the casual observer, but in reality, they had many subtle differences. The following data sheet contains the some data values regarding the KV-85 and IS-1 tanks that reveals some of them.

As we can see, there are some differences in the size of the tanks that accommodate the gun, as well as various features, most notably gun depression. The IS can depress the D-5 more than the S-31, and even though the KV-85 can depress the S-31 slightly more, the higher bore axis gives that gun a much larger dead zone. Additionally, 15 degrees of gun elevation is quite unacceptable for a breakthrough tank that is expected to fight in urban conditions.